Electromagnetic relay



March .13, 1928. 1,662,174

E. w. SEEGER ELECTROMAGNETIC RELAY Filed May 17. 1920 Patented Mar. 13, 1928.

UNITED STATES PATENT OFFICE.

EDWIN W. SEEGEB, OF MILWAUKEE, WISCONSIN, A SSIGNOB TO THE CUTLER-HAMMER MFG. (10., OF MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN.

nnnoraonaennrrc RELAY.

Application filed Kay 17, 1920. Serial No. 381,858.

This-invention relates to electromagnetic relays responsive to undulating currents.

In practice there are instances where a re-" lay adapted to respond at a given frequency of current supplied thereto but unresponsive at other frequencies of such current would he extremely advantageous and the present invention has among its objects to provide a simple and reliable relay to so function.

Another object is to provide a relay which may be readily designed and adjusted to vihratev at a given frequency of current supplied thereto and to be unresponsive at all higher frequencies. I

A further object is to provide an alternating current relay which is adaptedto respond only when the current supplied thereto is in a given direction and is at certain frequencies. Other objects and advantages of the invention will hereinafter appear.

The accompanying drawing illustrates two embodiments of: the invention which will now be described, it being understood that the embodiments illustrated are susceptible of various modifications without departing from the scope of the appended claims.

In the drawing, Figure 1 isaside elevational view of a preferred form of relay embodying the invention, and

Fig. 2 diagrammatically illustrates another embodiment of the invention.

The relay illustrated in Fig. 1 includes a stationary contact 1 and a cooperating contact finger 2 mounted onthe armature 3 of an electromagnetic winding 4, said stationary contact and said winding being mounted on the face of an. insulating panel '5. The winding 4 has a resistance 6 connected across the terminals thereof and said winding is provided with a magnetic frame 7 having poles 8 and 9, the former carrying the winding 4 and the latter having t e contact fin-' ger 2 and the armature 3 pivotally mounted pedance thereof, provlded the current in the thereon. Pole 9 is provided at its forward.

end with an upwardly curved extension 10 which carries an adjustable stop 11 for limiting outward movement of contact finger 2 and armature 3 under the action of an adjustable spring pressure device 12.

It will thus be observed that energization of winding '4 by an undulating current produces a flux tending to attract armature 3 against the action of spring pressure device 12 for movement of contact finger 2 into engagement with stationary contact 1. Fursupply circuit is of constant magnitude. As 'lS' well known the impedance of winding 4 varies directly as the fre uency of the current supplied thereto, and it is thus apparent that less current passes through said winding at higher frequencies than at lower frequencies. Thus with a given setting of the relay, winding 4 will effect response thereof at given frequencies but will he inoperative to effect response thereof at higher frequen-' cies.

The switch illustrated may he adjusted in various ways for variation of its sensitiveness through a wide range. For example, the sensitiveness of the relay may he varied by varying the size of the coil 4 and the value of resistance 6; b adjusting the air gap between pole 8 an armature 3 or by adjusting spring pressure device 12.

In some instances it is desirable to provide a relay which is adapted when connected in an alternating current circuit to respond when the instant pulsation of the current in said circuit is in a given direction and at certain frequencies and to remain unresponsive when the instant pulsation of the current in said circuit is in a reverse direction or at other frequencies. The aforedescribed relay can be readily modified to function in this manner by providing an additional winding 13 on pole 8 as shown diagram-, matically in Fig. 2. The winding 4 is connected 1n the alternating current circuit while the winding 13 is supplied with direct current. It will thus be observed that winding 13 has a polarizing effect or, in other words, the flux produced thereby assists the flux "in winding 4 in closing the relay when the pulsations in said latter winding are in one direction and opposes the flux lll it is apparent that for a given setting of the relay said winding when assisted by winding 13 will'eflect response of the relay at certain frequencies but will be inoperative to edect response thereof at other frequencies.

While the aforedescribed relays are responsive to, complete the circuit controlled thereby it is apparent that the same can be designed to break the controlled circuit upon response thereof. Also it is apparent that V the movable contact member will vibrate to make and break the controlled circuit if set to respond 'at relatively low frequencies while the same will remain in its attracted position if set to respond at higher frequen- ClES.

What ll claim as new and desire to secure by llrettersPatent is:

l.- A relay including an operating winding to be supplled with energy from a source of undulating current of variable frequency but substantially constant magnitude, and

, means associated with said winding for varyliiiill ll llilllllllllllllwmnum ing the flux produced thereby upon variations in the frequency of the current supplied thereto to render said relay responsive at given frequencies and unresponsive at other frequencies.

2. A relay including an operating winding to be en plied with energy from a source of undulatin current of variable frequency but substantia 1y constant magnitude and a shunt circuit for said winding including means for varying the flux produced by said winding upon variations in the frequency of the current supplied thereto to render said relay responsive at given frequencies and unresponsive at other frequencies.

3. A relay including an operating winding to be supplied with energy from a source of undulating current of varying frequency but substantially constant magnitude and a resistance connected across the terminals of said winding to render the same operative to actuate said relay at given frequencies and inoperative to actuate the same at higher frequencies.

4:. A relay including an operating winding to be supplied with energy from a source of undulating current of variable frequency but substantially constant magnitude and means associated with said winding to render the same operative to actuate said relay when the instant pulsation of current supplied thereto is in a given direction and of given frequencies and inoperative to actuate said relay when the instant pulsation of current supplied thereto is in reverse direction or at higher frequencies.

5. A relay including an operating windmeagre ing tobe supplied with energy from a source of undulating current of variable frequency but constant magnitude, a direct current winding for rendering said former winding inoperative to actuate said relay when the instant pulsation of current supplied thereto is in a given direction and a resistance connected 1n shunt to said former, windingof alternating current of substantiallycon stant magnitude for said winding, said resistance being adapted to render response of the relay dependent upon subjection of the latter to a given frequency of alternating current, and means for additionally rendering response of said relay dependent upon the direction of instant pulsation of current supplied thereto.

8. A relay com rising an operating winding to be supplie with energy from a source of alternating current of substantially constant magnitude, and a resistance connected in parallel with said winding whereby said winding when supplied with alternating current of a given value is rendered operative to actuate said relay when the instant pulsation is in a given direction and the current is of given frequencies and whereby the same is rendered inoperative to actuate said relay when the instant pulsation is in a reverse direction or the current is at higher frequencies. i

9. A relay comprising an operating winding to be supplied with energy from a source of alternating current of substantially constant magnitude, 0. direct current winding for rendering said former winding inoperative to-actuate said relay when the instant pulsation therein is in a given direction, and

a resistance connected in shunt to said first EDWIN W. serene. 

